(a) Technical Field
Aspects of the described technology relate to a non-volatile memory device.
(b) Description of the Related Art
Recently, according to a considerable increase in a storage capacity of a semiconductor memory device, competitiveness of the semiconductor memory device, which is capable of replacing an existing large data storage device including a hard disk, has gradually increased.
The semiconductor memory device is generally divided into a volatile memory device and a non-volatile memory device. When power of the non-volatile memory device is cut, the non-volatile memory device may maintain stored data without losing the data, and may be used as a storage device or a memory for a system. Recently, a flash memory device among the non-volatile memory devices is widely used as a large-capacity data storage device including a hard disk.
A memory cell array of the flash memory device may include a plurality of memory cell strings, and each of the memory cell strings may include a plurality of serially connected memory cells. A threshold voltage of the memory cell may be changed according to various operation conditions, and the changed threshold voltage causes a failure to read, thereby degrading reliability of the flash memory device. Accordingly, a technology for compensating for the degradation of reliability by the changed threshold voltage is required.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.